Diet can have a clear
effect on testosterone level, but it is less likely to be noticed in younger
men, whose testosterone levels are high anyway. However, testosterone levels
decline naturally as men become older, so the effects of diet on testosterone
can be more meaningful as men age into their forties and beyond.
A man’s testosterone level
drops by about 10% per decade. Symptoms of this decline can include a lower sexdrive, impaired sexual function, less energy and drive, reduced muscle mass and
physical strength, and increased body fat, especially around the waist. The
increase in erectile dysfunction with age is somewhat due to decreasing
testosterone level. It can also be related to blood flow restrictions to the
penis caused by disease processes. For example erectile dysfunction is much
higher among diabetics than among healthy men.
A 1997 scientific journal
article “Testosterone and cortisol in relationship to dietary nutrients and
resistance exercise” by Volek et al. of Penn State University, strongly linked
a man’s testosterone level to his diet. Among the male subjects studied, when
the following were higher in the diet, testosterone tended to be lower:
- protein intake as a percent of diet
- ratio of polyunsaturated to saturated fat
intake
- ratio of protein to carbohydrate intake
In contrast, when the
following were higher in the diet, testosterone tended to be higher as well:
- percentage of fat in the diet
- saturated fat intake per unit body weight
- monounsaturated fat intake per unit body weight
This study also showed a
weak negative effect of dietary fiber intake on testosterone level. Since other
studies found this as well, excess fiber intake may be considered a risk factor
for lowered testosterone levels.
These results are
important for several reasons. First, they highlight a tradeoff between eating
for health and longevity and eating to maintain male sexuality. A diet high in
saturated fats, while promoting testosterone production, is plainly contradictory
to the recommendations of the American Heart Association, which promotes a
lower fat diet. Also, the study contradicts the commonly-accepted notion that
eating more protein makes men more masculine. Body builders often eat great
quantities of low-fat protein yet have enormous muscles. Their high-protein,
low-fat diets might reduce their natural testosterone levels as a result, but
some of them make it up by taking steroids or testosterone supplements via
injection, pill, or skin-penetrating cream. However, in addition to several
other possible health effects, testosterone or steroid supplementation results
in shrinking of the testicles and reduction in the body’s natural testosterone
production. It can also cause infertility. Thus, maintaining and enhancing
one’s testosterone level naturally is clearly the preferred alternative. Even
though the study mentioned above revealed that some foods good for raising and
maintaining one’s testosterone level raise the risk of heart disease, it is
possible to select foods that are not detrimental to one’s health but still
facilitate the body’s testosterone production.
It isn’t necessary to eat
a low protein diet in order to promote testosterone production. A careful
examination of Volek’s article shows that only the men who ate extremely high
quantities of protein and who had exceptionally high protein-to-carbohydrate
intake ratios had lower testosterone levels. These individuals had great
influence on the statistical association. Without those subjects, the apparent
relationship of protein intake and protein-to-carbohydrate ratio to
testosterone level disappears. So, a man who ingests a healthy but not
excessive quantity of protein needn‘t be concerned. Daily protein consumption
of 2 grams per kilogram body weight (0.9 grams per pound body weight) supplies
plenty of protein for muscle growth and repair, as well as healthy body
function, without risking suppression of testosterone production.
As to the positive effect
of saturated fat intake on testosterone levels, one may ask whether it‘s worth
risking heart health by eating a lot of saturated fats such as those found in
fatty meats and full-fat dairy products in order to enhance testosterone
production. Fortunately, this is neither necessary nor prudent. Monounsaturated
fat, as found in olive or flaxseed oil and nuts, has the same positive effect
on testosterone level as saturated fat. So a man needn’t load up on fatty
meats, full-fat dairy products, or tropical oils in order to maximize his
testosterone. Liberal use of olive oil in cooking provides plenty of
monounsaturated fat. And a diet high in this good fat also promotes a healthy
HDL cholesterol level which helps prevent heart disease. In contrast, a high
saturated-fat diet can lead to arterial disease and directly cause erectile
dysfunction by reducing blood flow to the penis.
Another study published in
2000 examined the relationship between diet and SHBG, and found that
"diets low in protein in elderly men [40-70 years old] may lead to
elevated SHBG levels and decreased testosterone availability. The decrease in
bioavailable testosterone can then result in declines in sexual function and
muscle and red cell mass, and contribute to the loss of bone density."
Optimal Diet
If your purpose is to maximize testosterone levels to help increase muscle
tissue, your diet should be approximately 55 percent carbohydrates, 15 percent
protein and 30 percent fats. The danger is that a diet high in fats may
increase your risk of developing cardiovascular disease. If you prefer the
safer and more conservative approach, you can choose the alternative arrangement
as 50 percent carbs, 30 percent protein and 20 percent fats. Both diets are in
line with the Kappas study, which found that men given a high carb diet showed
higher testosterone levels than those given high protein diets.
Balanced diet is a key to the healthy life. Some modern extremists views
on the dietary restrictions might be trendy and appealing, but are quite
challenging, and in some cases, even dangerous to your health. In terms of
testosterone, Vegetarians will
experience a 14% reduction in testosterone levels, and vegans – even higher
losses. And your body really needs some saturated fat as well in order to produce
optimal levels of testosterone.
Sources and Additional Information:
